Haplogroup J2 (Y-DNA)

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In human genetics, Haplogroup J2 (M172) is a Y-chromosome haplogroup.

Haplogroup J2 is widely believed to be associated with the spread of agriculture from Anatolia [1],[2]. This connection is supported by its age (18,500 +/- 3,500 thousand years ago) [2], which is very close to the beginning of the Neolithic, its distribution, which is centered in West Asia and Southeastern Europe, as well as its association with the presence of Neolithic archaeological artifacts, such as figurines and painted pottery [3].

It is a descendant haplogroup of haplogroup J.

Contents

[edit] Distribution

Haplogroup J2 is found frequently in Greece and Italy [4], in Lebanon [2], in Turkey [1], and in the Caucasus region [5].

In Italy, one of the European countries with the highest frequencies of J2, it has been found in the remains of ancient Etruscans, who spoke a non-Indo-European language of unknown affinity. Another important fact about the distribution of Haplogroup J2 is that it appears to have dispersed from a Middle Eastern homeland to the west through a primarily maritime or littoral route, as it is found in high concentrations among the populations of the coasts of the Mediterranean Sea in both Eurasia and Africa, and particularly along the coasts of the eastern Mediterranean in Europe. This distribution may be more consonant with a Neolithic or post-Neolithic maritime dispersal from the Middle East, such as through Phoenician commercial and colonial activities, or even through Greek colonization following the presumed interaction between proto-Hellenes and Middle Eastern peoples that is suggested by ancient Greek legends, which attribute the founding of early cities in Greece to people of ancient Mesopotamian or other Middle Eastern extraction.

Jews and Arabs also possess J2, as do Kurds and other Middle Eastern populations [6]. Typically, these populations of the Middle East have a higher frequency of the related haplogroup J1, whereas the great majority of Haplogroup J representatives among the populations of Europe and India belong to the subclade J2. Haplogroup J2 has been shown to have a more northerly distribution in the Middle East when compared to its brother haplogroup, J1, which has a more southerly and particularly Semitic distribution. This suggests that, if the occurrence of Haplogroup J among modern populations of Europe, Central Asia, and South Asia does reflect Neolithic demic diffusion from the Middle East, the source population is more likely to have originated from Anatolia or northern Mesopotamia than from regions further south.

[edit] Subdivisions

Haplogroup J2 is subdivided into two complementary sub-haplogroups: J2a, defined by the M410 genetic marker, and J2b, defined by the M12 genetic marker. A subclade of haplogroup J2a, defined by the M92 marker has been implicated in the ancient Greek colonization [7].

[edit] See also

Human Y-chromosome DNA (Y-DNA) haplogroups
Y-most recent common ancestor
|
A |
B |
C | F
D E G H | K
I J L M | P
N O Q R

[edit] References

  1. ↑  C. Cinnioglu et al. (2004), Excavating Y-chromosome haplotype strata in Anatolia, Human Genetics 114(2):127-48.
  2. ↑  O. Semino et al. (2004), Origin, diffusion, and differentiation of Y-chromosome haplogroups E and J: inferences on the neolithization of Europe and later migratory events in the Mediterranean area, American Journal of Human Genetics 74(5):1023-34.
  3. ↑  R. King and P.A. Underhill (2002), Congruent distribution of Neolithic painted pottery and ceramic figurines with Y-chromosome lineages, Antiquity 76:704-714
  4. ↑  F. Di Giacomo et al. (2003), Clinal patterns of human Y chromosomal diversity in continental Italy and Greece are dominated by drift and founder effects, Molecular Phylogenetics and Evolution 28(3):387-95.
  5. ↑  I. Nasidze et al. (2003), Testing hypotheses of language replacement in the Caucasus: evidence from the Y-chromosome, Human Genetics 112(3):255-61.
  6. ↑  Sanghamitra Sengupta et al. (2006), Polarity and Temporality of High-Resolution Y-Chromosome Distributions in India Identify Both Indigenous and Exogenous Expansions and Reveal Minor Genetic Influence of Central Asian Pastoralists, American Journal of Human Genetics, 78:202-221
  7. ↑  Renfrew, A.C. (1987). Archaeology and Language: The Puzzle of Indo-European Origins, London: Pimlico. ISBN 0-7126-6612-5
  8. ↑  A. Nebel et al. (2001), The Y chromosome pool of Jews as part of the genetic landscape of the Middle East, Americal Journal of Human Genetics 69(5):1095-112.
  9. ↑  F. Di Giacomo et al. (2004), Y chromosomal haplogroup J as a signature of the post-neolithic colonization of Europe, Human Genetics 115(5):357-71.

[edit] External links

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